Apparatus for molding hollow plastic articles

ABSTRACT

Apparatus for molding hollow plastic articles such as bottles comprises a rotor driven in one direction, with a plurality of separable mold assemblies with complementary cavitated mold halves articulated for opening and closing and mounted in circumferential alignment on the rotor, adapted while travelling a circular path therewith to register seriatim with a plastics extruder. Motivating means operable cyclically in the rotation of the rotor open each of the mold assemblies sequentially before reaching the extruder to release molded articles and while still open and upon registering with the extruder to receive plastic material therefrom, the motivating means then acting to close the mold assemblies for molding the thus received plastic material. The mold assemblies are substantially permanently mounted on the rotor and have replaceable cavity inserts facilitating changeovers. A method of molding blown hollow plastic articles in a continuous string with ribbed integral connecting links.

United States Patent [72] Inventor William S. Pearson 2,750,624 6/1956Coates et a1. 18/5 BN X Hampstead, Mtl. 3,305,891 2/1967 Nozaki 18/5 BP[2]] Appl. No. 838,074 3,310,834 3/1967 Simpson et a1 18/5 BP [22] FiledJuly 1, 1969 3,402,431 9/1968 Fogelberg et a1. 18/5 BB X [45] PatentedJan. 4, 1972 P E R b rt L S J [73] Assignee Cypro Incorporated "mary f oe P Hampstead, Mm Attorney-Hill, Sherman, Meronr, Gross & Simpson [54]APPARATUS FOR MOLDING HOLLOW PLASTIC ABSTRACT F F 9" 1 such as bottlescomprises a rotor drlven m one direction, with ARTICLES 30 Claims 1 1Drawing Figs a plurality of separable rnold assemblies withcomplementary cavitated mold halves articulated for opening and closingand [52] U-S.C| 425/151, mounted in ircumferential alignment on therotor, adapted 4 24, 425/342, 42 /4 2 while travelling a circular paththerewith to register seriatim [5 l Int. Cl B29d 23/03, with a plasticsextruder, Motivating means operable cyclically B 1/ B290 in the rotationof the rotor open each of the mold assemblies [50] Fleld of Search 18/5BB, 5 qu ntially before reaching the extruder to release molded 5 BF, 55 5 5 20 20 articles and while still open and upon registering with theex- 20 K RR; 264/97 truder to receive plastic material therefrom, themotivating 56 R f ed means then acting to close the mold assemblies formolding 1 e erences the thus received plastic material. The moldassemblies are UNITED STATES PATENTS substantially permanently mountedon the rotor and have 2,515,093 7/1950 Mills 18/5 BN replaceable cavityinserts facilitating changeovers. 2,579,399 12/ 1951 Ruehberg 18/5 B1 Amethod of molding blown hollow plastic articles in a continuous stringwith ribbed integral connecting links.

Z4 1 1|- 1 f e z 1 J] g 19 r a] g Z! I y (y 160 2a l I 17 :0 ll 15 r J140 139 I o 6 1 5a 30 I .94 (I 58 F g7 i 33 l I i M 1 1 fl n I l 1 \i 3%y 4 1 74 v [I I] [A] o n Q] a l 75 1 Il ,e\ e $8 a 7 71 11 27,

APPARATUS FOR MOLDING HOLLOW PLASTIC ARTICLES This invention relates toapparatus for molding hollow plastic articles, and is more particularlyadapted for relatively high speed blow molding of plastic bottles, andthe like.

I-Iollow plastic articles have generally been produced in single ofmulticavity molds by injection of thermoplastic material or by extrusioninto the molds in a step and advance manner. Such prior expedients havebeen slow and cumbersome and the coat of individual molded articles hasnecessarily reflected the limitations upon productivity.

Another disadvantage in prior apparatus has been that the molds whichare generally water cooled have required unduly long shutdown ofproduction machines when articles of different size or configuration areto be made on the same machine, requiring laborious uncoupling andrecoupling of water ducts, and the like.

The foregoing and other disadvantages, deficiencies and shortcomings ofprior apparatus are overcome in a highly efficicnt and advantageousmanner and with marked economy and greatly increased productivity by thepresent invention which provides apparatus adapted to operate at highspeed to produce articles continuously and which when it is desired tochange or replace any one or all of the molds minimum downtime orstoppage of production is necessary and far less than as heretofore beencustomary.

It is, accordingly, an important object of the present invention toprovide new and improved article molding apparatus of superiorefficiency, increased reliability, greatly improved operatingperformance and producing capacity, ease and simplicity of adjustmentfor production accuracy, and significantly increased speed ofproduction.

Another object of the invention is to provide a new and improved plasticarticle molding machine which is adapted for highspeed continuous blowmolding of plastic articles connected together in articulated series forconvenience in stripping from the molds of the machine operatingseriatim.

A further object of the invention is to provide new and improved plasticarticle molding apparatus having a novel arrangement of separable moldsmounted on a rotor for seriatim registration with a plastics extruder.

Still another object of the invention is to provide new and improvedmeans in rotary plastic article molding apparatus for operating a seriesof separable molds for highspeed, highproduction operation.

Yet another object of the invention is to provide new and improvedplastic article molding apparatus with novel means for effecting quickchange in the molding dies whereby to greatly minimize downtime for theapparatus.

A still further object of the invention is to provide a new and improvedmethod of molding plastic articles in a continuous separable string.

Other objects, features and advantages of he invention will be readilyapparent from the following description of the certain preferredembodiments thereof, taken in conjunction with the accompanyingdrawings, although variations and modifications may be effected withoutdeparting from the spirit and scope of the novel concepts of thedisclosure, and in which:

FIG. 1 is a perspective view of apparatus embodying features of theinvention;

FIG. 2 is an enlarged fragmentary perspective view of the apparatusdisclosing the cooperative relationship thereof to and with a plasticsextruder;

FIG. 3 is a fragmentary enlarged perspective view of the apparatusshowing in greater detail how molded plastic articles are stripped fromthe separable molds;

FIG. 4 is a rear perspective view of the apparatus;

FIG. 5 is a schematicoperating circuit diagram;

FIG. 6 is a side isometric view of one of the mold-actuating assembliesof the apparatus showing the same in various open mold positions;

FIG. 7 is a similar side isometric view showing the mold actuatingdevice in the closedmold position;

FIG. 8 is a fragmentary plan view taken substantially along the lineVIII-VIII of FIG. 7;

FIG. 9 is a fragmentary elevational and sectional view takensubstantially along the line IX-IX of FIG. 8;

FIG. 10 is a plan view of the bottom half of a cavity mold according tothe present invention; and

FIG. 11 is an end elevational view looking toward the left in FIG. 10.

Referring to FIG. 1, molding apparatus is shown comprising a rotor 15having means for driving it in one direction of rotation and havingmeans thereon individually mounting in circumferential alignment aplurality of separable cavity mold assemblies I7 and adapted whiletravelling a circular path with the rotor to register seriatim with aplastics extruder 18. Motivating means are provided operable cyclicallyin the rotation of the rotor 15 to open each of the mold assembliessequentially before reaching the extruder for releasing molded articles19 from the molds, and while the molds are still open and upon reachingregistration with the extruder plastic material is received from theextruder thereinto. The motivating means then acts to close the moldsfor molding the plastic material into the articles 19.

In order to facilitate stripping of the articles 19 from thesuccessively opened molds, and subsequent handling of the articles tofinishing apparatus, the articles are connected in an articulated chainwith an integralconnecting link 20 between each article and the nextadjacent article in the chain. From the molds 17, the chain of articles19 may be trained over a takeoff wheel 21 keyed to a rotary shaft 22driven in unison with the rotor 15 by suitable means such as a flexibledrive connection 23. On the stripper wheel are transversepropelling bars24 spaced to receive the articles 19 therebetween at the links 20 forpropelling the chain in stripping relation to the underlying moldassemblies 17.

There may be as many of the mold assemblies in cooperativecircumferential alignment on the rotor I5 as may conveniently beutilized. In the arrangement shown 10 such mold assemblies have beenused. Each of the mold assemblies 17 comprises complementary articulatedhalves 25 and 27 (FIGS. 1, 2 and 3) which are mounted to be swung openand closed. For this purpose, each of the mold halves includes a similarbody block which may be made of suitable metal such as steel oraluminum. In their confronting faces, the body blocks of the mold halves25 and 27 are provided with complementary matching molding cavities 28and 29, respectively. Inasmuch as the plastic material may be suppliedat a relatively high temperature such as up to 220F. to facilitatemolding, it is necessary for highspeed operation to provide a coolingsystem which will circulate a coolant such as water through the moldbody blocks to chill the molded articles sufiiciently to beselfsustaining upon release from the molds. For this purpose, it hasbeen customary to provide the mold body blocks with chambers or passagesfor circulating the coolant. Herein coolant supply ducts 30 such asflexible hoses are suitable connected to the respective die body blocks25 and 27, and each of the blocks is provided with a suitable pattern ofcoolant circulation passages 31, such passages being indicated in FIGS.10 and 11 in the mold body blocks 25, but it will be understood that asimilar arrangement is in the mold body blocks 27. Coolant circulationis effected from a suitable pressurized supply such as a tank 30athrough a rotary coupling assembly 32 on a hollow front end portion 33(FIG. 1) of a rotary shaft 34 by which the rotor 15 is mounted, and incommunication with which the ducts are connected.

In order to enable quick change in the mold assemblies 17 for differentarticles or different sizes of articles, without necessitatingdetachment of the various coolant ducts or removal of the mold bodyblocks 25 and 27 from the machine, and which would require many hours ofnonproductive downtime for the machine where all of the molds must bechanged, the mold cavities 28 and 29 are provided in respective quicklyreplaceable inserts 35 and 37. Each of the cavity inserts 35 and 37 isconstructed as an elongated transversely rectangular block having therespective mold cavity upon in one face thereof and with the cavityblock seated in a respective complementary longitudinal recess 38 in theassociated mold body block and separated from the coolant passages 31 tothat changes can be made without draining the coolant circulationsystem. Installation of the cavity insert section blocks 35 and 37 isquickly effected by setting the same into its receiving recess 38 in theassociated mold body block and then locking the blocks firmly togetherin not only the effective operating relation but also thorough heattransfer relation. Desirably this is effected by having the bottom andone side surface of the cavity insert block machined to make closeface-toface contact with the bottom and one side surface of thereceiving recess 38. At the opposite side an elongated wedge 39 (FIGS.2, 3, and 11) is driven in firm retaining and heat transfer relationagainst and between the side of the cavity block and the adjacent sideof the receiving cavity as well as against the bottom of the cavity anddesirably comprises a highheat transfer capacity material such as bronzewhich works very well especially where both the mold body block and theinsert block are of aluminum. To enhance these features, the wedge 33 isat least as long as the associated mold body block and desirably alittle longer, with the wedgereceiving side of the receiving recesstapered complementary to the wedge taper for receiving the wedge with anendwise tapped in, tightlocking engagement. For retaining the wedgeagainst unintentional displacement, it is desirably locked in place by aretaining screw 41 and a washer 42. As further assurance againstdisplacement of the cavity insert block 35 a retaining screw 43 andwasher 44 are desirably provided fastened into the mold body block andgripping the cavity insert block in a clearance recess 45 at the sideopposite to the wedgeengaged surface, with the parting face of thecavity insert block sufficiently spaced beyond the adjacent face of themold body block to afford ample clearance for the heads of the retainingscrews 41 and 43 when the confronting parting faces of the complementarycavity insert blocks 35 and 37 are brought into firm moldclosedrelation. Further, it will be noted that the respective sets ofretaining screws 41 and 43 associated with the insert blocks 35 and 37are relatively offset or staggered for closedmold clearance. Removal ofthe respective insert blocks 35 is readily effected by reversal of theinstallation steps. Through this arrangement it has been found possibleto remove and reinstall a complete set of activity insert blocks in a10- mold machine in about 1 hour.

In structure and relationship the mold cavity sections 28 and 29 and theinsert blocks 35 and 37 are such that there is efficient circumferentialalignment thereof in the molding phase of the machine cycle. To thisend, while the mold body blocks 25 are separated at their ends as shown(FIGS. 1, 2 and 3), the respective opposite ends of the insert blocks 35extend substantially beyond the ends of the associated mold body blocksto about the respective ends of the companion insert blocks 35 at leastat their parting face edges, and desirably throughout the adjoining endsfor strength and stability. For this purpose the respective oppositeends of the insert blocks 35 are appropriately complementally chamfered.This enables the supporting mold body blocks 25 to be stationarilymounted on and about the rotor 15, while the mold body blocks 27 and thecavity inserts 37 carried thereby are mounted to be swung between openand closed relation to the relatively stationary mold halves. Fulllengthregistration of the cavity inserts 37 with the respective opposed cavityinserts 35 is effected by having the parting faces of the cavity insertblocks 37 complementary in length to make full contact with theconfronting parting faces of the insert blocks 35. At their oppositeends, the insert blocks 37 may extend beyond the respective oppositeends of the supporting mold body blocks 27.

To enable individual adjustment of each of the mold assemblies 17 foroptimum performance, to avoid transmission of distorting stresses orstrains from one assembly to the other when and if they occur, and toenable mounting of different size molds when required, construction andarrangement of the rotor 15 is such that each of the mold assemblies isindividually mounted and motivated. To this end there is provided foreach of the mold assemblies 17 an individual, adjustable and replaceablemounting beam 47 (FIGS. 1, 6 and 7) disposed in a respective radialplane parallel with the axis of the shaft 34 and attached at each endfor adjustment in such plane relative to the shaft. In its front endportion, the beam is provided with a parallel arm, slotprovidingbifurcated portion 48 which at its outer end straddles athreadedsupporting rod 49 extending radially relative to the shaft 34and having an end anchored fixedly in a respective socket 50 in acorotative collar 51 on the shaft. Optimum substantially micrometeradjustment of the front end of the beam as well as major radialadjustments are thus enabled by suitable manipulation of adjustment nuts52 by and between which the opposite edges of the beam section 48 areengaged. At its opposite or rear end, the beam 47 is radially adjustablyattached to a combination mounting disk and rotor driving wheel 53(FIGS. 4 and 6) which is corotatively mounted on the shaft 34. For this,the beam 47 has a radial fin terminal 54 engaged in selectively radiallyslidably adjustable relation in a respective radial groove 55 providedtherefor in the adjacent face of the disk 53, with securing bolts 57extending through respective vertical slots 58 aligned with the groove55.

Attachment of the mold body blocks 25 to their respective beams 47 is bymeans of respective mounting baseplates 59 fixedly attached to the beamportions 48 as by means of screws 60. The blocks 25 are adapted to besecured to the baseplates 59 by means of screws 25a (FIGS. 1t) and 11)engaged in screw holes 60a in the plates.

Mounting of the mold body blocks 27 on the beams may also be on andthrough the mounting plates 59, but in a manner to enable articulatedmovement of the mold bodies 27 relative to the mold bodies 25. For thispurpose, an articulating hinge structure 61 is mounted on each of theplates 59 rearwardly adjacent to the mold body block 25 in each instanceand hingedly supports a baseplate 62 to which the mold block 27 issuitably secured as by means of screws 63. Desirably the hinge structure61 comprises an assembly of rod ends 64 relatively pivotally connectedby a hinge pin 65 and with threaded end portions of respective pairs ofthe rod ends adjustably attached to the respective plates 59 and 62 asby means of respective pairs of nuts 67. Through this arrangement,highly accurate parting face closing engagement of the mold halves andmore particularly the cavity insert sections is attainable.

For motivating the hinged mold halves, a combination fluid actuator andlever system is provided comprising a rectilinear cylinder 68 having apiston operated reciprocable piston rod 69, with the rear end of thecylinder pivotally secured through a clevis 70 thereon to the attachmentear 54 of the beam. At its outer end, the piston rod 69 has a clevis 71pivotally attached to he outer end of a rocking motivating lever 72 ofgenerally L- shape having a shorter leg thereof located within theslotted front end portion 48 of the beam and extending forwardly andattached pivotally thereto by a pin 73 subjacent the mounting plate 59.Extending forwardly from the outer end portion of the lever 72 is an arm74 related in generally C clamp, but spaced relation to the mountingplate 62 and connected at its outer end thereto by means of a pair ofparallel links 75 pivoted at one of their ends to the arm 74 and attheir opposite ends to a rigid car 77 on the mounting plate 62. Throughthis arrangement, actuation of the actuator 68, 69 effects rocking ofthe lever 72 and through the arm and link connection with the plate 62effects substantially movement of the mounting plate 62 and thereby themold body 27 supported thereby from a closed-mold position to a fullyopen position, as may be visualized on comparison of the dash lineposition of FIG. 6 with the full line showing in FIG. 7. As will also beobserved in FIG. 7, in the closed position the links 75 extend normal tothe plane of the mounting plate 62 and thus normal to the plane of theassociated articulated mold half, and the lever 72 has its pivot 73aligned with the axis of the links in the closed position so that a C-clamp latching action results which positively holds the mold closedagainst blowing apart during molding. Since molding pressures are thuseffectively resisted extremely close parting face contact of the cavityinsert blocks is assured and parting joint flash is avoided on themolded articles. On the other hand, by virtue of the link connection 75,should there be an obstruction to closing of the mold, completion ofmoldclosing stroke of the actuator 68, 69 will be effectively resistedwithout damage to the mold assembly.

For optimum operating adjustment of the link 75 with respect to themounting plate 62, the arm 74 is mounted to be longitudinally adjustablealong the lever 72. For this purpose, the arm 74 comprises a pair ofcomplementary plates 74a and 74b engageable with a longitudinal dovetail78 (FIG. 8) along the edge of the lever 72. Longitudinal adjustmentmovement of the arm 74 along the dovetail is adapted to be effected bymeans of an adjustment screw 79 (FIG. 9) carried by the arm andthreadedly engageably within a halfthreaded groove 80 along thedovetail. Adjusted position is maintained by clamping the dovetailplates 74a and 74b as by means of bolts 81 whereby to hold the screw 79and the dovetail firmly gripped against unintentional displacement ofthe arm.

By preference, pneumatic operation of the actuator 68, 69 is providedfor because of the inherent yieldability of compressed air so that anyobstruction between a mold half or possibly overloading of the mold willnot result in damage to the mold or the motivating means. Nevertheless,under proper operating conditions, the C- clamp lever and link mechanismwill effectively lock the mold against separation due to acceptablemolding pressures. To this end, each of the actuator cylinders 68 hasconnected thereto adjacent to its opposite ends suitable air hoses 82which are connected to a compressed air source through control mechanismfunctioning to operate the actuators in proper sequence to open andclose the associated mold assemblies. For this purpose, the airhoses 82for each of the actuators are connected to a respective doubleactingvalve 83 (FIGS. 4 and 5) which are desirably mounted on the back of themounting disk and rotordriving wheel 53 and to which compressed air isdelivered through a common duct 84 connected to the air source through adistributor 85 carried corotatively on the shaft 34 and receiving airthrough a rotating joint having a housing 87 fixedly mounted at the rearside of a bearing 88 for the shaft. To the joint air is delivered by aduct 89 connected through an oil injector 90 and a pressure gauge 91with an air tank 92 (FIG. 1) to which a suitable air compressor (notsown) is operatively connected. Each of the valves 83 is of the kindhaving a reciprocable movable plunger 93 having suitable rollers on itsopposite ends. Movement of the plunger 93 in one direction effectsmoldclosing operation of the associated actuator, and movement of theplunger in the opposite direction effects moldopening operation of theassociated actuator.

Operation of the valves 83 is effected in the rotation of the wheel 53which is driven continuously at the desired operating speed for therotor by means such as a drive chain 94 trained over the toothedperimeter of the wheel and over a driving sprocket 95 on a shaft 97extending drivingly from a gearbox 98 and driven by a suitableelectrical motor 99 which may be controlled from a control panel 100 onthe front portion of a frame 101 carrying the bearings in which therotor shaft 34 is joumaled. It will be observed (FIG. 4) that the takeoff or stripper wheel drive chain 23 is driven in unison with themounting disk and driving wheel 53 by a sprocket wheel 102 corotativewith the rear end portion of the shaft 34.

Each of the valves 83 is mounted with its plunger 93 on an axis radialto the axis of the shaft 34 so that respective valve plunger shiftingdevices mounted alongside the back of the wheel 53 will operate thevalves in proper timed sequence. For this purpose, a moldclosing valveactuator 103 in the form of a finger is mounted in the path of advanceof the valves 83 theretoward to depress each of the valve plungers 93 asit passes the control finger. Conveniently, the control finger 103 isadjustably mounted on a radially extending arm 104 carried by a fixedsupporting annulus 105 mounted through brackets 107 on the machine frame101. In order to adjust the supporting arm 104 in a circumferentialdirection for proper timing of the valve operation, the arm has amounting annulus gripping structure 108 including a tightening block 109operated through a screw 110. By loosening the screw 110 the am 104 canbe adjusted on and about the annulus 105 to the optimum valve operatingpssition. Air exhausting from the valves 83 is directed by means ofsuitable ports 111 toward the drive chain 94 to impinge lubricating oilentrained in the air onto the chain. Absorbent pads 112 are desirablymounted adjacent to the ports 11 1 to catch surplus oil.

For reversing each of the valves 83 sequentially to open the successivemolds, a valveactuating device 113 is mounted at the proper place on themounting annulus 105 spaced from the moldclosing operator, andconstructed and arranged for adjustment circumferentially on theannulus. A valve-actuating element 114 is carried by the device 113along the inner perimeter of the mounting annulus 105. A tighteningblock 115 carried by the device 113 enables the device to be fixed inthe properly adjusted position. Through this arrangement, as therespective valves 83, which are equally spaced circumferentially on thewheel 33 successively pass the respective valve shifters, the moldmotivating actuators are responsively operated to respectively close themolds and to open the molds in proper sequence.

For blowing the articles 19 to size within the respective mold cavities,each of the articulates mold halves is provided with an air injectinghypodermic needle 117 (FIGS. 2, 3 and 5) mounted on a plunger 118operated by a piston 119 mounted reciprocably within a cylinder 120 andnormally retracted by a compression spring 121 but adapted to be drivenin a protractional stroke by air pressure supplied to the cylinderthrough a duct 122 from a valve 123 connected to a supply line 124communicating with a distributor 125 (FIGS. 4 and 5) on the shaft 34adjacent to the distributor 85. Compressed air as free as practicablefrom oil or moisture is supplied to the distributor 125 through thecoupling 87 which is of dual passage form for this purpose, by way of aduct 127 suitably communicating with a source of air pressure. Each ofthe cylinders 120 is mounted by means of a bracket 128 on the associatedmounting plate 62, with the hypodermic needle 117 extending throughsuitable aligned bores in the mold body block 27 and the cavity block37. In practice the needle 117 may have a stroke of about fiveeighthsinch between a mold cavity clearing, retracted position and an articleblowing protracted position wherein the needle penetrates to he hollowinterior of the article in the mold.

Sequential operation of the hypodermic needlecontrolling valves 123 iseffected similarly as has been explained in respect to themoldmotivating mechanism control valves 83. To this end, each of thevalves 123 is mounted on the backface of the wheel 53, desirably inpaired proximity to one of the valves 83 and in a relatively offsetplane relationship thereto such that the valve-operating finger 103 willbe cleared by respective rollercarrying reciprocable valvecontrollingplungers 128 of the valves 123 in the rotation of the wheel 53, but avalveoperating arm 129 will shift the plungers 128 in proper timedrelation after closing the respective mold assemblies 17 to pressurizethe blowing needle cylinders 120 to project the associated needle 117into article blowing position wherein the air pressure utilized fordriving the needle is also bled through the piston 119 and the plunger118 into and through the needle 117 into the article. Supporting thevalveactuating finger 129 is a radialmounting arm 130 mounted forcircumferential adjustment on the supporting annulus 105 and having amounting yoke 131 provided with a tightening block 132. In order todisable the valveoperating finger 129 quickly for emergency purposes orwhen it is desired to effect adjustments, or when for any other reasonit is desired to maintain any of the successive hypodermic needle unitsinactive, or even the entire system inactive in any one or more machinecycles, a handled lever 133 is provided on the mounting structure forthe finger 129 so that the finger can be quickly swung out of valveoperating position to an inactive position, but can be just as quicklyreturned to the active position by swinging the lever 133 back to theoperating position.

After article blowing has been completed and a sufficient molding cycletime interval has elapsed, the valves 123 are reversed to shutoff theair pressure and to exhaust air from the needle cylinders 120 so thatthe biasing spring 121 will retract the respective needles. For thispurpose, a valve-operating device 134 is provided carried by a yoke 135mounted for circumferential adjustment on the carrying annulus 105 andretained in adjusted position by a tightening block 137 secured by asetscrew 138. As the respective valves 123 pass the valveoperator 134,the plungers 128 are returned to the air shutoff and needle cylinderexhausting condition of the affected valve 123.

In operation, the molding machine rotor is so located with respect tothe extruder 18 that plastic material to be molded is received by therespective open mold assembles 17 from a downwardly delivering extruderhead 139 FIG. 2). This head is provided with suitable heating means 140such that a continuous tubular thermoplastic parison 141 will descend atthe proper temperature and rate of gravity elongation as extruded fromthe head. Extrusion rate may be at relatively high speed by virtue ofthe close location of the parisonreceiving mold assemblies 17 to thepoint of extrusion, as enabled by the full 90 opening of the molds byvirtue of the novel motivating means already described. Thereby, theopen halves 27, 37 of the molds are adapted to pass closely alongsidethe extruder head 139 (FIG. 3) and the successive molds to receive theparison 141 move into position closely under the extruder head 139 andupon reaching a vertical position the open half of the mold is free toswing closed onto the parison to engage the same within the closedcavity 28, 29 and whereupon the hypodermic needle 117 associated withthe mold is activated to blow the parison from the initial smallerdiameter to a larger blown diameter with the mold cavity.

In the illustrated instance, the molded articles 19 are disclosed asbottle blanks. For this purpose, the cavity sections 28 and 29 haverespective matching bottle body portions of maximum diameter andbottleneck forming portions of smaller diameter at one end of the bottlebody cavity portion. Each of the cavity sections also has a matchingextension 142 (FIG. 2, 3 and 10) which provides on the bottle blank neckportion a blowing head extension 143 receptive of the blowing airhypodermic needle 117 in each instance, which after molding has beencompleted leaves a characteristic entry hole 144 in the head 143. Thisportion of the blank is adapted to be subsequently trimmed ofi inbottlefinishing apparatus.

Formation of the connecting links 20 of the molded article string iseffected in a manner to afford several advantages. At one end, the link21) is connected to the head end of the associated pair of bottle blanksby a thin hinge web 145 and at its opposite end the web is connected tothe base end of the other bottle of the connected pair by a thin hingeweb 147. These hinge webs enable relatively free hinging of therespective blanks about the hinge axes at each end of the link tofacilitate stripping of the blanks from the molds and running of thechain or string of blanks over the stripper and takeoff wheel 21, aswell as subsequent handling of the string. Between the hinge webs 145and 147, the respective connecting links 20 are desirably relativelyrigid but with a practical minimum of material whereby to maintain theamount of scrap at a low level, and to enable complete curing of thelinks in the curing time interval for the article blanks. Further, inthe formation of the links 211, means are provided to enable gauging byvisual inspection as to whether the proper amount of plastic materialshas been supplied per article unit by the extruder, namely, to checkwhether the extruder is in proper parison rate synchronism with themolding apparatus. To this end, the cavity section blocks 35 and 37 haveconnecting tab or linkforming arrangements comprising at one end of themold cavity section block 35 a link molding portion 148 having atjuncture with the cavity section 28 a hinge webfonning surface area 149tapering therefrom. The remainder of the molding portion 148 from thearea 149 to the adjacent end of the parting face cooperates with ashallow matching link tab thickness governing cavity recess 150 (FIGS. 2and 3) in the confronting end portion of the parting face of theassociated cavity section block 37 and which is defined at the adjacentend of the main articlemolding cavity section 29 by a hinge webformingarea 151 which coacts with the area 149. To minimize the amount ofmaterial in the link 20 and yet provide a sufficiently rigid linkstructure for the intended purpose, the molding portion 148 is providedlongitudinally therealong with spaced parallel transversely extendinggrooves 152 which are desirably of sufficient length to permitunhampered outward movement of plastic therein, and which are connectedby a center longitudinal, but desirably shallower, groove 153 runningout at the end of the parting face.

At the opposite end portion of the cavity block 35, a similar connectinglinkmolding extension 154 is provided with a hinge webforming area 155at juncture with the head end portion 142 of the molding cavity. Thisportion 154 is provided longitudinally therealong with ribformingtransverse spaced parallel grooves 156 and a connecting longitudinalshallower groove 157 for the same purposes as the similar grooves in thelinkmolding portion 148 and, in effect, provid ing an extension from theportion 148 on the parting face of the cavity block 35 of the nextadjacent mold assembly. In the matching parting face of the cavity block37, a shallow link thickness governing connecting linkforming cavityrecess 158 cooperates with the portion 154, and a hinge webshaping area159 cooperates with the area 155.

By virtue of the grooves arrangement of the linkmolding portions 148 and154, each of the links is formed with corresponding transverse ribs 160and a connecting longitudinal rib 161. By observing the length of therespective ribs 160, visual indication of the amount of material in theparison 141 can be readily gauged. If the rate of plastic materialdelivery is too slow, the link ribs will show underdevelopment, whereasif the rate of delivery is too fast, the link ribs will show overdevelopment. Suitable adjustment of the extruder speed can then readilybe made to cure the outofbalance in plastic delivery without shuttingdown the machine. Any of the articles in the string which may haveunacceptable wall structure due to any extruder maladjustment may bediverted to scrap until the proper amount of material is provided in theparison as revealed by observing development of the ribs 160, namely,whether not too long or too short. The multirib structure of theotherwise relatively thin section of the tab links 20 facilitatesregrinding when they become scrap.

In addition, by having the material of the tab links 20 engaged withinthe forming grooves 152, 153, 156, 157 increased cooling contact withthe mold section insert blocks 35 and 37 is attained so that thoroughhardening occurs before the mold is opened, avoiding any wet tabcondition in the connected article string.

To assure uninterrupted development of the ribs 160, relatively shallowair bleed grooves 162 are provided as extension from the grooves 152 and156 to the respective opposite edges of the parting face of the cavityblock 35. In addition the bleedoff or vent grooves 162 assure that whereexcessive material is supplied at the link forming portions of themolds, no excessive back pressure will develop which would inhibitproper closing of the molds.

In order to shut down the machine and the extruder automatically in theevent of a failure to properly strip the molded articles from the openmolds, a safety switch device 163 (FIG. 2) is provided having a trip arm164 disposed to project over the mold cavities 28 in a positionimmediately after the molded article has been stripped therefrom. Shouldthe article 19 not be stripped from the mold or if there is an undue lagin stripping, the actuator finger 164 will be engaged and trip theswitch to shut down the machine and the extruder.

it may also be noted that the molding cavities are provided at the outerends of the extensions 142 with generally rectangular respectiveenlargements 165 (FIGS. 2, 3, l and 11) which provide correspondingheads 167 on the molded article blanks. These heads 167 are useful inproviding handling shoulder and orientation or indexing means in thepostmolding processing of the blanks.

In order to avoid the air entrapment in the coolant circulation passages31 in the mold blocks 25 and 27 when the machine is shut down, the ducts30 are so connected to the hollow distributor 33 that the ducts leadingto the mold assemblies 17 which are at any time at the top of thecircuit have their connections into the lower portion of the distributor33. As a result, any air present in the distributor 33 during shut downwill be prevented from rising into the uppermost mold assemblies whereit might remain trapped and impair efficiency but will remain trapped inthe distributor and will then be readily purged from the system when themachine is again operated and circulation resumed.

I claim as my invention:

1. In apparatus for molding hollow plastic articles such as bottles andincluding a rotor mounted on a horizontal axis and having means whichdrive it in one direction of rotation, said rotor comprising:

a plurality of separable mold assemblies each of which has complementarycavitated mold halves articulated for opening and closing the assembly;

respective generally horizontal beams individually mounting saidassemblies in circumferential alignment about the rotor axis and adaptedin rotation of the rotor toregister seriatim with a plastics extruder;and

motivating means on said beam operable cyclically in the operation ofthe rotor for opening said mold assemblies sequentially before reachingthe extruder to release molded articles and while still open and uponreaching registration with the extruder to receive plastic materialtherefrom, the motivating means then acting to close the mold assembliesfor molding the thus received plastic material.

2. Apparatus according to claim 1, including means adjustably connectingeach of said beams individually in the rotor for adjustment radiallyrelative to the rotor axis, said beam and the mold assemblies as well assaid motivating means being thereby adjustable in unison relative tosaid axis by a simple adjustment of the respective beams.

3. Apparatus according to claim 1, said rotor having a shaft, meansjournaling the shaft, and means attaching opposite end portions of saidbeams to the shaft.

4. Apparatus according to claim 3, said attaching means comprisingstructure enabling adjustment of the position of each beam independentlyradially relative to the shaft.

5. Apparatus according to claim 4, said structure comprising arespective radially extending adjustment screw for determining theradial disposition of one end portion of each beam relative to theshaft, and the opposite end of the shaft having mounted thereon acoaxial fixed annular structure to which the attaching means structuresat the opposite end portions of the beams are secured in radiallyadjustable relation.

6. Apparatus according to claim 1, said motivating means comprisingrespective generally 0 shaped lever structure pivotally mounted on eachbeam operatively connected to the respective mold assembly and rockablebetween a mold assembly closing position and a mold assembly openingposition.

7. Apparatus according to claim 6, including a respective linkconnecting each lever structure with its associated mold assembly.

8. Apparatus according to claim 7, the link coacting with the leverstructure and the mold assembly as a positive holding latch to preventblowing open of the mold assembly during molding.

9. Apparatus according to claim 8, including a respective fluidoperatedactuator connected at one end to the lever structure and at the oppositeend to the respective beam.

iii

10. Apparatus according to claim 8, comprising means effectingconnecting of said link to and between said lever structure and saidmold assembly preventing movement of the link into latching relation tothe associated mold assembly, as a safety feature, if there is anobstruction to proper closing of the mold assembly.

11. Apparatus according to claim 8, said lever structure includingrelatively adjustably connected parts to one of which said link isconnected.

12. Apparatus according to claim 1, each of said mold assemblies havingcomplementary cavitated mold halves, hinge means connecting said moldhalves, and means for adjusting said hinge means to enable optimumclosing relation of said halves.

13. Apparatus according to claim 1, each of said mold assembliesrespectively comprising separable mold halves, means securing one ofsaid mold halves in stationary relation to the associated beam, meanspivotally mounting the other of said mold halves on and relative to saidbeam and relative to the stationarily mounted mold half, the beam havinga slot therein underlying said stationarily mounted mold half, saidlever structure having an end portion thereof in said slot and pivotallyconnected to the beam subjacent the stationarily mounted mold half, saidlever structure having a further end portion thereof superjacent thepivotally mounted mold half, and means connecting the superjacent endportion of the lever structure with said pivotally mounted mold half toeffect substantially 9U pivotal movement of said pivotally mounted moldhalf between fully closed and fully open positions.

14. Apparatus according to claim 13, said means connecting thesuperjacent end portion of the lever structure to the pivotally mountedmold half comprising a link operative in the fully closed position ofthe mold assembly to lock the same against opening.

15. Apparatus according to claim 13, including a fluidoperated actuatorconnected at one end to said lever structure adjacent to saidsuperjacent end portion and connected at its opposite end to said beam.

16. Apparatus according to claim 13, said superjacent end portioncomprising an arm, and means adjustably securing said arm to theremainder of the lever structure.

17. Apparatus according to claim 16, said means connecting thesuperjacent end portion with said pivotally mounted mold half comprisinga link pivotally connected to said mold half and to said arm.

18. Apparatus according to claim 1, wherein said mold assemblies eachcomprise separable mold body blocks, means providing fluid circulatingsystem in each of said blocks, respective matching mold cavity blocksections having respective parting faces which are adapted to be abuttedto provide a mold cavity one portion of which is in one of said sectionsand the remaining portion of which is in the other of said sections, andmeans separately securing said cavity sections respectively to the moldblocks separated from said circulation means to enable replacement ofsaid sections without interfering with said circulation means andwithout requiring removal of the body blocks from said beams.

19. Apparatus according to claim 18, each of said mold body blockshaving a'cavity sectionreceiving recess therein into which therespective cavity section is engaged, and respective wedge means lockingsaid sections as inserts in said recesses.

20. Apparatus according to claim 19, said cavity sections having theirparting faces projecting in offset relation to parting faces of saidbody blocks, said wedges being in said recesses and engaging betweenopposed surfaces of said sections and said body blocks, and additionallocking means on said body blocks engaging said wedges and said cavitysections and leaving said parting faces of said sections free to engagein close abutment in the closed position of the mold assembly.

21. Apparatus according to claim 1, said mold assemblies each comprisingseparable mold halves each of which has one portion of a mold cavity andwhich portions match in a closed position of the mold halves, said moldhalves having portions thereof extending beyond opposite ends of saidmolding cavity portions and provided with respective shallowconnectinglinkmolding extensions from said cavity potions and opening from therespective opposite ends of confronting parting faces of said mold halfend portions to join with companion mold assemblies joined endtoend formolding a continuous string of plastic articles connected together byintervening connecting links, said shallowlink molding extensions havingat juncture with the molding cavity portions confronting shaping areasoperative to mold thin flexible connecting hinge webs joining the moldedarticles with the connecting links.

22. Apparatus according to claim 21, said sballowconnecting link moldingcavity portions including spaced transverse grooves to shape transverseribs in said connecting links.

23. Apparatus according to claim 22, said mold halves having ventgrooves therein shallower than said rib grooves and connecting the ribgrooves with edges of said parting faces.

24. Apparatus according to claim 1, said mold halves having coolantpassages therein, respective coolant supply ducts having connectionswith said passages, said rotor having a shaft including a coolant supplydistributor, and connections securing the ducts in communication withsaid distributor in such relation as to be on the low side of thedistributor when the mold assemblies are high on the rotor.

25. Apparatus for molding hollow plastic articles such as bottlescomprising:

a rotor having means which drive it in one direction or rotatron;

a plurality of separable mold assemblies each of which has complementarycavitated mold halves articulated for opening and closing the assembly;

means individually mounting said assemblies in circumferential alignmenton said rotor and adapted while travelling a circular path therewith toregister seriatim with a plastics extruder;

motivating means operable cyclically in the rotation of the rotor foropening said mold assemblies sequentially before reaching said extruderto release molded articles and while still open and upon reachingregistration with the extruder to receive plastic material therefrom,the motivating means then acting to close the mold assemblies formolding the thus received plastic material;

said motivating means comprising individual fluidoperated actuators forsaid mold assemblies;

means for supplying said actuators with operating pressure fluid;individual valves for controlling the supply of pressure fluid to saidactuators;

a valve mount carried corotatively by said rotor;

a stationary member located adjacent to said mount;

valve operators carried by said stationary member for operating saidvalves in cyclical sequence;

each of said valves comprising a reciprocable plunger;

said stationary member comprising an annulus coaxially disposed aboutthe axis of said rotor;

said valve operators comprising radial arms circumferentially adjustablymounted on said annulus and each having a valve actuating devicethereon;

one of said arms having the valve actuating device thereon disposed tobe operable to move the valve plungers in one direction and another ofsaid arms having the valve actuating device operable to shift the valveplungers in the opposite direction.

26. Apparatus for molding hollow plastic articles such as bottlescomprising:

a rotor having means which drive it in one direction of rotation;

a plurality of separable mold assemblies each of which has complementarycavitated mold halves articulated for opening and closing the assembly;

means individually mounting said assemblies in circumferential alignmenton said rotor and adapted while travelling a circular path therewith toregister seriatim with a plastics extruder;

motivating means operably cyclically in the rotation of the rotor foropening said mold assemblies sequentially before reaching said extruderto release molded articles and while still open and upon reachingregistration with the extruder to receive plastic material therefrom,the motivating means then acting to close the mold assemblies formolding the thus received plastic material;

each of said mold assemblies having a hollow plastic article blowingdevice;

means for supplying the blowing devices with compressed individualvalves for controlling operation of said blowing devices;

a mount corotatable with said rotor and carrying said valves;

a stationary member adjacent to said mount;

valve operating assemblies carried by said stationary member foroperating said valves sequentially in timed relation with saidmotivating means;

each of said valves comprising a reciprocable plunger;

said stationary member comprising an annulus coaxially disposed aboutthe axis of said rotor;

said valve operators comprising radial arms circumferentially adjustablymounted on said annulus and each having a valve actuating devicethereon;

one of said arms having the valve actuating device thereon disposed tobe operable to move the valve plungers in one direction and another ofsaid arms having the valve actuating device operable to shift the valveplungers in the opposite direction.

27. ln apparatus for molding hollow plastic articles such as bottles andincluding a rotor mounted on a horizontal axis and having means whichdrive it in one direction of rotation, said rotor comprising:

a plurality of separable mold assemblies each of which has complementarycavitated mold halves articulated for opening and closing the assembly;

respective generally horizontal beams individually mounting saidassemblies in circumferential alignment about the rotor axis and adaptedin rotation of the rotor to register seriatim with a plastics extruder;

motivating means on said beams operable cyclically in the operation ofthe rotor for opening said mold assemblies sequentially before reachingthe extruder to release molded articles and while still open and uponreaching registration with the extruder to receive plastic materialtherefrom, the motivating means then acting to close the mold assembliesfor molding the thus received plastic material;

each of said mold halves comprising a mold body block,

means fixedly securing one of said body blocks to the associated beam;

means pivotally connecting the other of the body blocks to the fixedlysecured body block;

means for circulating coolant fluid through each of said body blocks;

each of said blocks having a recess therein separated from the coolantsupply means;

respective mold cavity insert blocks received in said recesses; and

means securing said insert blocks replaceably in said recesses enablingremoval and replacement of the insert without disturbing said fluidcirculating means and without requiring removal of said mold body blocksfrom said beam.

28. Apparatus according to claim 27, said recesses opening throughopposite ends of said body block and said cavity inserts having endportions with project from the recesses beyond the ends of therespective body blocks.

29. Apparatus according to claim 27, said recesses opening through atleast one end of the respective body block, said means securing saidinsert blocks replaceably in the recesses comprising respective wedgeshaving end portions extending beyond the ends of said recesses tofacilitate driving the same into right relation to the insert block.

30. Apparatus according to claim 29, including means locking said wedgesagainst unintentional displacement.

1. In apparatus for molding hollow plastic articles such as bottles andincluding a rotor mounted on a horizontal axis and having means whichdrive it in one direction of rotation, said rotor comprising: aplurality of separable mold assemblies each of which has complementarycavitated mold halves articulated for opening and closing the assembly;respective generally horizontal beams individually mounting saidassemblies in circumferential alignment about the rotor axis and adaptedin rotation of the rotor to register seriatim with a plastics extruder;and motivating means on said beams operable cyclically in the operationof the rotor for opening said mold assemblies sequentially beforereaching the extruder to release molded articles and while still openand upon reaching registration with the extruder to receive plasticmaterial therefrom, the motivating means then acting to close the moldassemblies for molding the thus received plastic material.
 2. Apparatusaccording to claim 1, including means adjustably connecting each of saidbeams individually in the rotor for adjustment radially relative to therotor axis, said beam and the mold assemblies as well as said motivatingmeans being thereby adjustable in unison relative to said axis by asimple adjustment of the respective beams.
 3. Apparatus according toclaim 1, said rotor having a shaft, means journaling the shaft, andmeans attaching opposite end portions of said beams to the shaft. 4.Apparatus according to claim 3, said attaching means comprisingstructure enabling adjustment of the position of each beam independentlyradially relative to the shaft.
 5. Apparatus according to claim 4, saidstructure comprising a respective radially extending adjustment screwfor determining the radial disposition of one end portion of each beamrelative to the shaft, and the opposite end of the shaft having mountedthereon a coaxial fixed annular structure to which the attaching meansstructures at the opposite end portions of the beams are secured inradially adjustable relation.
 6. Apparatus according to claim 1, saidmotivating means comprising respective generally C-shaped leverstructure pivotally mounted on each beam operatively connected to therespective mold assembly and rockable between a mold assembly closingposition and a mold assembly opening position.
 7. Apparatus according toclaim 6, including a respective link connecting each lever structurewith its associated mold assembly.
 8. Apparatus according to claim 7,the link coacting with the lever structure and the mold assembly as apositive holding latch to prevent blowing open of the mold assemblyduring molding.
 9. Apparatus according to claim 8, including arespective fluid-operated actuator connected at one eNd to the leverstructure and at the opposite end to the respective beam.
 10. Apparatusaccording to claim 8, comprising means effecting connecting of said linkto and between said lever structure and said mold assembly preventingmovement of the link into latching relation to the associated moldassembly, as a safety feature, if there is an obstruction to properclosing of the mold assembly.
 11. Apparatus according to claim 8, saidlever structure including relatively adjustably connected parts to oneof which said link is connected.
 12. Apparatus according to claim 1,each of said mold assemblies having complementary cavitated mold halves,hinge means connecting said mold halves, and means for adjusting saidhinge means to enable optimum closing relation of said halves. 13.Apparatus according to claim 1, each of said mold assembliesrespectively comprising separable mold halves, means securing one ofsaid mold halves in stationary relation to the associated beam, meanspivotally mounting the other of said mold halves on and relative to saidbeam and relative to the stationarily mounted mold half, the beam havinga slot therein underlying said stationarily mounted mold half, saidlever structure having an end portion thereof in said slot and pivotallyconnected to the beam subjacent the stationarily mounted mold half, saidlever structure having a further end portion thereof superjacent thepivotally mounted mold half, and means connecting the superjacent endportion of the lever structure with said pivotally mounted mold half toeffect substantially 90* pivotal movement of said pivotally mounted moldhalf between fully closed and fully open positions.
 14. Apparatusaccording to claim 13, said means connecting the superjacent end portionof the lever structure to the pivotally mounted mold half comprising alink operative in the fully closed position of the mold assembly to lockthe same against opening.
 15. Apparatus according to claim 13, includinga fluid-operated actuator connected at one end to said lever structureadjacent to said superjacent end portion and connected at its oppositeend to said beam.
 16. Apparatus according to claim 13, said superjacentend portion comprising an arm, and means adjustably securing said arm tothe remainder of the lever structure.
 17. Apparatus according to claim16, said means connecting the superjacent end portion with saidpivotally mounted mold half comprising a link pivotally connected tosaid mold half and to said arm.
 18. Apparatus according to claim 1,wherein said mold assemblies each comprise separable mold body blocks,means providing fluid circulating system in each of said blocks,respective matching mold cavity block sections having respective partingfaces which are adapted to be abutted to provide a mold cavity oneportion of which is in one of said sections and the remaining portion ofwhich is in the other of said sections, and means separately securingsaid cavity sections respectively to the mold blocks separated from saidcirculation means to enable replacement of said sections withoutinterfering with said circulation means and without requiring removal ofthe body blocks from said beams.
 19. Apparatus according to claim 18,each of said mold body blocks having a cavity section-receiving recesstherein into which the respective cavity section is engaged, andrespective wedge means locking said sections as inserts in saidrecesses.
 20. Apparatus according to claim 49, said cavity sectionshaving their parting faces projecting in offset relation to partingfaces of said body blocks, said wedges being in said recesses andengaging between opposed surfaces of said sections and said body blocks,and additional locking means on said body blocks engaging said wedgesand said cavity sections and leaving said parting faces of said sectionsfree to engage in close abutment in the closed position of the moldassembly.
 21. Apparatus according to claim 1, said mold assemblies eachcomprIsing separable mold halves each of which has one portion of a moldcavity and which portions match in a closed position of the mold halves,said mold halves having portions thereof extending beyond opposite endsof said molding cavity portions and provided with respectiveshallow-connecting link-molding extensions from said cavity portions andopening from the respective opposite ends of confronting parting facesof said mold half end portions to join with companion mold assembliesjoined end-to-end for molding a continuous string of plastic articlesconnected together by intervening connecting links, said shallow-linkmolding extensions having at juncture with the molding cavity portionsconfronting shaping areas operative to mold thin flexible connectinghinge webs joining the molded articles with the connecting links. 22.Apparatus according to claim 21, said shallow-connecting link moldingcavity portions including spaced transverse grooves to shape transverseribs in said connecting links.
 23. Apparatus according to claim 22, saidmold halves having vent grooves therein shallower than said rib groovesand connecting the rib grooves with edges of said parting faces. 24.Apparatus according to claim 1, said mold halves having coolant passagestherein, respective coolant supply ducts having connections with saidpassages, said rotor having a shaft including a coolant supplydistributor, and connections securing the ducts in communication withsaid distributor in such relation as to be on the low side of thedistributor when the mold assemblies are high on the rotor. 25.Apparatus for molding hollow plastic articles such as bottlescomprising: a rotor having means which drive it in one direction orrotation; a plurality of separable mold assemblies each of which hascomplementary cavitated mold halves articulated for opening and closingthe assembly; means individually mounting said assemblies incircumferential alignment on said rotor and adapted while travelling acircular path therewith to register seriatim with a plastics extruder;motivating means operable cyclically in the rotation of the rotor foropening said mold assemblies sequentially before reaching said extruderto release molded articles and while still open and upon reachingregistration with the extruder to receive plastic material therefrom,the motivating means then acting to close the mold assemblies formolding the thus received plastic material; said motivating meanscomprising individual fluid-operated actuators for said mold assemblies;means for supplying said actuators with operating pressure fluid;individual valves for controlling the supply of pressure fluid to saidactuators; a valve mount carried corotatively by said rotor; astationary member located adjacent to said mount; valve operatorscarried by said stationary member for operating said valves in cyclicalsequence; each of said valves comprising a reciprocable plunger; saidstationary member comprising an annulus coaxially disposed about theaxis of said rotor; said valve operators comprising radial armscircumferentially adjustably mounted on said annulus and each having avalve actuating device thereon; one of said arms having the valveactuating device thereon disposed to be operable to move the valveplungers in one direction and another of said arms having the valveactuating device operable to shift the valve plungers in the oppositedirection.
 26. Apparatus for molding hollow plastic articles such asbottles comprising: a rotor having means which drive it in one directionof rotation; a plurality of separable mold assemblies each of which hascomplementary cavitated mold halves articulated for opening and closingthe assembly; means individually mounting said assemblies incircumferential alignment on said rotor and adapted while travelling acircular path therewith to register seriatim with a plastics extruder;motivating means opeRably cyclically in the rotation of the rotor foropening said mold assemblies sequentially before reaching said extruderto release molded articles and while still open and upon reachingregistration with the extruder to receive plastic material therefrom,the motivating means then acting to close the mold assemblies formolding the thus received plastic material; each of said mold assemblieshaving a hollow plastic article blowing device; means for supplying theblowing devices with compressed air; individual valves for controllingoperation of said blowing devices; a mount corotatable with said rotorand carrying said valves; a stationary member adjacent to said mount;valve operating assemblies carried by said stationary member foroperating said valves sequentially in timed relation with saidmotivating means; each of said valves comprising a reciprocable plunger;said stationary member comprising an annulus coaxially disposed aboutthe axis of said rotor; said valve operators comprising radial armscircumferentially adjustably mounted on said annulus and each having avalve actuating device thereon; one of said arms having the valveactuating device thereon disposed to be operable to move the valveplungers in one direction and another of said arms having the valveactuating device operable to shift the valve plungers in the oppositedirection.
 27. In apparatus for molding hollow plastic articles such asbottles and including a rotor mounted on a horizontal axis and havingmeans which drive it in one direction of rotation, said rotorcomprising: a plurality of separable mold assemblies each of which hascomplementary cavitated mold halves articulated for opening and closingthe assembly; respective generally horizontal beams individuallymounting said assemblies in circumferential alignment about the rotoraxis and adapted in rotation of the rotor to register seriatim with aplastics extruder; motivating means on said beams operable cyclically inthe operation of the rotor for opening said mold assemblies sequentiallybefore reaching the extruder to release molded articles and while stillopen and upon reaching registration with the extruder to receive plasticmaterial therefrom, the motivating means then acting to close the moldassemblies for molding the thus received plastic material; each of saidmold halves comprising a mold body block, means fixedly securing one ofsaid body blocks to the associated beam; means pivotally connecting theother of the body blocks to the fixedly secured body block; means forcirculating coolant fluid through each of said body blocks; each of saidblocks having a recess therein separated from the coolant supply means;respective mold cavity insert blocks received in said recesses; andmeans securing said insert blocks replaceably in said recesses enablingremoval and replacement of the insert without disturbing said fluidcirculating means and without requiring removal of said mold body blocksfrom said beam.
 28. Apparatus according to claim 27, said recessesopening through opposite ends of said body block and said cavity insertshaving end portions which project from the recesses beyond the ends ofthe respective body blocks.
 29. Apparatus according to claim 27, saidrecesses opening through at least one end of the respective body block,said means securing said insert blocks replaceably in the recessescomprising respective wedges having end portions extending beyond theends of said recesses to facilitate driving the same into right relationto the insert block.
 30. Apparatus according to claim 29, includingmeans locking said wedges against unintentional displacement.